This invention relates to fire retardant polystyrenic compositions.
For many uses, fire retardant additives have been incorporated into polystyrenic compositions, such as polystyrene, acrylonitrile-butadiene-styrene copolymers (ABS resins), high-impact polystyrenes and the like, to impart fire resistance to such compositions. Organic compounds containing bromine and/or chlorine and/or phosphorous are employed frequently as fire retardant agents. Nitrogen compounds, such as bromoanilines, brominated diphenylamines and anilides, generally in admixture with chlorinated paraffins, have also been suggested as fire retardants.
The synergistic action of combinations of fire retardant additives has also been contemplated with a view toward decreasing the amount of fire retardant agent which is required to obtain polystyrenic compositions which fulfill specifications relating to combustion and flame propagation. Such combinations of additives are most often oxides or sulfides of heavy metals, more particularly antimony oxide, having a synergistic action with halogenated fire retardant agents. When used alone or in the absence of any halogenated fire retardant agent, antimony oxide has no fire retardant action.
An object of the present invention is to provide a new synergistic fire retardant additive combination for fire retardant compounds.
An additional object of the present invention is to provide a synergistic combination of additives for producing fire retardant polystyrenic compounds which generally are used in admixture with antimony oxide.
Another object of the present invention is to provide new and improved fire retardant and anti-static polystyrenic compositions.